单项选择题 You create a Microsoft ASP.NET application by using the Microsoft .NET Framework version 3.5. You add a TextBox control named TextBox1.  You write the following code segment for validation：   protected void CustomValidator1_ServerValidate（object source， ServerValidateEventArgs args） {   DateTime dt = String.IsNullOrEmpty（args.Value） ？ DateTime.Now ： Convert.ToDateTime（args.Value）；   args.IsValid = （DateTime.Now - dt）.Days < 10；   }   You need to validate the value of TextBox1.  Which code fragment should you add to the Web page？ （）

单项选择题 You create a Microsoft ASP.NET application by using the Microsoft .NET Framework version 3.5. You create a composite custom control named MyControl.  You need to add an instance of the OrderFormData control to the MyControl control.  Which code segment should you use？（）

单项选择题 You create a Microsoft ASP.NET application by using the Microsoft .NET Framework version 3.5. You create the following controls：  a composite custom control named MyControl. a templated custom control named OrderFormData.   You write the following code segment to override the method named CreateChildControls（） in the MyControl class：   01 protected override void CreateChildControls（）  02 {   03   Controls.Clear（）；   04   OrderFormData oFData = new   05     OrderFormData（"OrderForm"）；   06   07 }    You need to add the OrderFormData control to the MyControl control.  Which code segment should you insert at line 06？ （）